Stylized Fur Creation

Let me start of as a true party-pooper and point out that none of those characters where designed, modeled, covered in fur and rendered by a single person during a coffee brake (although while the final scene is rendering, you’ll probably have enough time for a good cup of java). Having given you that advice, please disregard it – because we’re going to try to do so anyway.

Given that carton or stylized animals generally are quite clear-cut and unfussy in there design, the time spent on adding fine details such as wrinkles and creases can usually be kept to a minimum. Basically, all you have to is to get a cube and start moving the points around till you’re happy with shape. Sounds simple enough, right? Well, even if the technical side of the modeling isn’t necessarily more complicated than so, it is the very same simplicity that makes it challenging. As you chuck out most of the details you stand a great risk of ending up with a rather meaningless and uninteresting character, which is pretty much the opposite of what you’ve original planed.

When you design the character it’s essential that the audience should be able to distinguish the species without having to think about it. However, this does not mean you should stay true to its real life counterpart for the entire body. On the contrary, just keeping (and preferable exaggerate) one or two of the main characteristics and then do something completely unexpected with the rest of the body is usually a very good way to start. While you’ll hopefully end up with a unique design for your character, gathering references before you start is still a vital part of the process. Not only for making sure that you, at least in some sense, stay true to reality but perhaps more importantly to serve as inspiration. So, this is important, do not limit your references to only include the specific animal you have in mind.

With somewhere in the line of 10 to 14 milliard different existing species on earth alone, there’s a slight chance you’ll be able to find a couple of interesting animals for you to mix and match to your liking. Seeing this is a quite hefty amount to go through, for your convenience, we went ahead and did so and didn’t stop until we hade found the perfect animal. Dear reader, over the next three pages we give you… the Anteater.

The project files and the original tutorial as it appeared in 3D World can be found at http://www.computerarts.co.uk/tutorials/3d__and__animation/how_do_i_create_ice_age-like_hairy_characters_in_xsi

STAGE ONE Getting in to character
Step 01
The first thing you’ll obviously need in order to complete the following steps is an undressed creature willing to experience a total hair makeover. We recognize these can be shy creatures and therefore somewhat rare to come by so if you don’t already have one of your own, start by loading the scene anteater.scn from this issues CD.
Step 02
While using several hair generator operators enables you to use specific settings and hair count for each part, you’ll run it to problems with discontinuity between the different clusters, which basically means that you’ll get nasty seems in the fur. So unless you’re planning on having substantial different characteristic on the fur for the different parts of the body, you’ll be better of using a single hair operator for the entire anteater.
Step 03
While the anteater will end up completely covered by fur, there are a couple of areas where you don’t want/need any hair such as inside the eye sockets, inside the nose and the matrices. Select the anteater and press [Y] to activate the polygon selection tool. Select all the polygons and zoom in on the above mentioned areas and deselect just those polygons.

STAGE TWO Growing hair
Step 04
With the polygons still selected, press [Ctrl] + [2] to switch to the Hair toolbar and from the Hair > Create > Hair menu choose From Selection. It would be unfeasible to modify and style each single hair strand by hand so a guide hair is created at each vertex on character. As you style the hairs XSI will automatically interpolate between the guides, creating a perfect fur.
Step 05
Apart from being way to long, all the strands currently have the exact same length as well, which isn’t very realistic. So the first thing you need to do is to give him a rough haircut. Make sure the hair is still selected, and from the Modify > Length menu choose Attenuate. This will cut the hair in relation to the size of the polygon it’s being emitted from. Smaller polygons will get shorter strands and vice versa. Apply a second Attenuate operator.



Step 06
While you can use the standard scale tool on your hair, it will not affect the actual length of the strands but rather change their position and orientation. To change their length you’ll need to use either the Scale or Cut operator from the Hair toolbar. An alternative is to activate the Stretchy mode, although we won’t be using this in the walkthrough feel free to experiment with it on your own.





Step 07
The hair along the back of his neck, the eye sockets and most of the snout where cut a bit to short whereas the one on the chin (or beard) is way to long. Set the selection filter in the Select panel to Strand. Select each part (or sections of them) and Scale (using the scale button in the Hair toolbar) them to roughly match the above screenshot.
Step 08
The hair on the waist, thigh and at the end of the tail is a bit to short as well, so make them slightly longer using the same procedure as in the previous step. You can always change the length later on as well, so don’t worry if it doesn’t look exactly like the screenshots. Conclude the cutting session by selecting the strands under his feet and scale them so they won’t protrude the ground.
Step 09
Unless your hairdresser is truly gifted (and your hairstyle can be described as mysterious at best) you really don’t expect her to cut and style your hair in a wink of an eye. Nor that she’ll do the entire tuft in a single go. Nevertheless, that’s precisely what a lot of people expect as they enter their virtual barber. Unfortunately, there’s no magic button for creating nice looking fur - you’ll just have to be patient throughout the following steps.

STAGE THREE Combing the fur

Step 10
Instead of combing the fur manually with, the for example, the Brush tool you can make use of the camera viewport. Click the Strand button in the Selection panel and select all the strands on the snout. Now, in the Camera viewport track and orbit so you’re looking down the snout from just behind the eye sockets. From the Modify > Comb menu choose Comb Away From Camera View B
Step 11
Next select all the strands on the body, except the mane (the strands running along the back), and rear legs. Position the camera (viewport) on top of the anteater. Orbit the camera a bit vertical so you’re looking downward but at a slight angle. From the Modify > Comb menu choose Comb Away From Camera View B
Step 12
Select the strands on the rear legs, position the camera above and slightly behind the character and choose Comb Away From Camera View B. Please refer to the screenshot at step 15 to get the general idea of how to comb the fur for the different parts of the anteater (a high resolution version of the screenshots can be found on this issues CD).
Step 13
Finally, select the strands on the tail, position the camera so you’re looking along the tail choose Comb Away From Camera View B. Please note that you can get even more control of the combing procedure by selecting smaller section of strands within each of the different parts of the body. Alter the camera slightly differently for each selection to create a smother blend between the parts.
Step 14
As you begin styling your character the hair operator’s history stack will build up very quickly. Each modification to the hair gets added to the stack as a styling operator and will sooner or later have a negative affect on the scene performance. Therefore, remember to freeze the hair operator from time to time or simply switch to the immediate mode by pressing the Immed button in the Edit panel.

STAGE FOUR Ruffle the fur
Step 15
Now you’ve got the strands running more or less along the right directions on the body but they’re still far to perfect to come of as convincing fur. Seeing that the carton anteater is a rather joyful species we can safely assume that his fur will be all tousled during most part of the day. While you can add this effect (to a certain extent) in the hair operator PPG it will just add to overall appearance by having the actual strands ruffled as well.
Step 16
While there’s a number of tools dedicated solitary for hair styling, you’re by now mean limited to these alone. On the contrary, utilizing alternative styling methods such as the standard deformers can produce not only quicker but also, more importantly, better results. Select all the hair strands and press [1] to switch to the Model Toolbar. From the Modify > Deform menu chose Randomize.
Step 17
While you’ve got the strands selected it’s in fact the same as selecting all the points and this is precisely what you want to randomize. Since you’ve just gone trough the lengthy process of combing the fur you really don’t want to mess that up. You just want to randomize it enough to make look as if it has been worn. A value of about 0.15 for the X, Y and Z Displacement should do the trick nicely.
Step 18
While the fur now has a far more natural look, some of the strands are going trough body. To fix this, switch back to the Hair Toolbar. Select the protruding strands (preferable not all at once) and chose the Modify > Puff > Puff Roots and/or the Modify > Puff > Strand On End and click and drag in the viewport. Or you can use the standard translation tool. Remember, you’re trying to create natural irregularities so it doesn’t have to be perfect.

STAGE FIVE The Hair PPG
Step 19
Select the hair and press [Enter] to open the hair PPG. Depending on how close you get, you’ll need to increase the number of Total hairs to 150.000 - 300.000 to completely cover the anteater in fur. To make the fur denser, you can also make use of the Hair Multiplicity. This multiplies each hair strands but requires less memory and will be faster to render as they’re copies of the original strands rather than “completely unique”.




















Step 20
However, to keep the rendering time as low as possible during the development of the fur it’s wise to leave the number of rendered hairs quite low till you render the final image. Switch to the Effects tab. Set the Frizz at root to about 25, the Frizz at tip to 75 and increase the Frequency to 75. Next, set the Root Thickness to 0.4 and the Tip to 0.1. And finally, set the Random scale to about 0.5.




















Step 21
The character isn’t particularly smooth at the moment, so select the anteater and press [+] to increase subdivision one level. While the geometry is subdivided, the hair is still emitted from the low resolution version. Press [8] to open an Explorer and expand the tree, including the Hair operator. Click on the Hair Generator Operator to open the PPG and change the Emitter Subd Level to 1.

STAGE SIX Dyeing the fur




















Step 22
Select the anteater and press [1] to switch to the Model Toolbar. From the Get > Property > Texture Map menu chose Texture Map. Chose the projection from the Projection List in the UV Property. Open an Explorer expand the hierarchy. Switch back to the Hair Toolbar and select both the hair operator and the anteater. In the Hair Toolbar, click the Transfer Map button and pick the Texture_Map in the Explorer




















Step 23
The previous step transferred the texture projection from the anteater to the hair, enabling you to use textures to color the fur. Select the hair and press [7] to open a Render Tree. Get an image node (Node > Texture) and two Color Correction nodes (Node > Image Processing) and connect them according to the above screenshot. Double click on the Hair Render node to open the PPG and copy the values shown in the screenshot.
Step 24
Double click on the Image node and load the image anteater_color.pic. Open the CC connected to the Root input set the Saturation to 0.1 and the level to -0.2. This will make the Root color slightly darker, creating an illusion of depth. Next, open the CC connected to the TipB and set the saturation to -0.1 and the level to 0.1. This will make the Tip color B a bit more pale, creating a nice variation on the fur. Texturing the anteater with the same image (or a darker version) will hide any minor bald spots. Finally, add a couple of lights, and enable the shadows for the main light as this will add greatly to appearance of the fur. Please note that no animals were harmed during the making of this Q&A.

Quick tip
Don’t get stuck with minor details (or strands) to early on in the process as there’s a great chance you’ll be gong back and forth making changes to the fur as you progress.